Locate and complete the secret mission at the end of the game.
Complete all levels in the game on normal difficulty or higher.
Complete all the levels in the game on the highest difficulty.
Complete all levels in the WW2 campaign.
Complete all levels in the Civil War campaign.
Complete all levels in the WW1 campaign.
Punch a horse in the face, killing it.
Complete a combat level without using any lethal attacks.
Kill at least 25 NPCs with your bare hands.
Die of suffocation underwater.
Kill yourself with an explosive device.
Fully upgrade all pistol settings.
Fully upgrade all rifle settings.
